JP3396174B2 - Vehicle seat lifter device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat lifter for a vehicle, and more particularly to a structure for supporting a seat up and down by using a spring brake device and a link mechanism so that the seat can be moved up and down. Regarding improvements in things. 2. Description of the Related Art In many cases, a front seat of a vehicle is provided so as to be able to move up and down with respect to a vehicle body floor in order to secure an optimum driving posture of a driver. A rotatable link connects the left, right, front and rear of the seat pan on which the cushion is mounted, and a base plate provided on the upper rail of the seat slide device mounted on the vehicle body, and meshes with a sector gear for rotating the link. A vehicle seat lifter device configured by fixing a spring brake device having a pinion to a base plate is adopted. [0003] In a spring brake device, a shaft having a coaxially cutout circular drum called a core is rotatably supported in a cylindrical housing fixed to a base plate, and an outer peripheral surface of the drum and a cylindrical housing are rotatably supported. A coil spring is interposed between the inner peripheral surface of the drum and the inner peripheral surface of the cylindrical housing. A pinion, which is formed integrally with an engagement protrusion that forms a gap between both ends of the coil spring and protrudes into the cutout portion of the drum, is axially attached to one end of the shaft. And it is formed by attaching an operation handle to the other end of the shaft. Therefore, when the operating handle is rotated, the engaging projection rotates while the diameter of one end of the coil spring is reduced by the rotation of the shaft during normal rotation, so that the sector gear is meshed with the pinion. Is rotated to raise the link and raise the seat pan from the base plate. [0005] Here, when the occupant is seated on the seat cushion and the load is applied, a force for rotating the sector gear in the opposite direction is generated through the link, so that the pinion meshing with the sector gear is disengaged. The shaft tends to rotate in the reverse direction, but the engaging protrusion expands the diameter of one end of the coil spring, so that the coil spring comes into pressure contact with the inner peripheral surface of the cylindrical housing and generates large frictional resistance.
The friction resistance prevents the shaft from rotating in the reverse direction, thereby locking the set seat cushion height. When the height of the seat cushion is to be changed downward, the shaft is rotated in the reverse direction by rotating the operation handle in the opposite direction, and the core reduces the diameter of the other end of the coil spring. By releasing the pressure contact with the inner peripheral surface of the cylindrical housing, the reverse rotation of the shaft is allowed and the reverse rotation of the pinion is enabled, so that the seat cushion and the seat pan descend integrally toward the base plate. Met. [0007] In recent vehicle designs, a vehicle seat lifter device has
Improvements based on demands such as downsizing due to a decrease in hip points and expansion of the ascending / descending range are required. [0008] However, to increase the range of elevation, it is necessary to increase the size of the sector gear or the operating angle of the sector gear.
Although there are various methods, the increase in the size of the sector gear contradicts the above-mentioned demand, so that it is inevitable to take a method of increasing the operating angle of the sector gear. Therefore, based on such a design concept, the link and the sector gear are fully extended at the highest position of the seat pan, that is, the rotation shaft of the sector gear and the engagement of the sector gear and the link. The shaft and the rotation axis of the link are aligned in a straight line. In this state,
The load due to the occupant and the seat itself acts toward the center of the shaft, and does not act in the direction of rotating the sector gear. That is, in the vicinity of the highest position, the frictional force generated by pressing the sector gear against the rotating shaft is larger than the rotational force for rotating the sector gear (frictional force> rotational force). When the operating handle is turned to lower the seat pan, the other end of the coil spring is turned by the rotation of the shaft while reducing the diameter of the other end, and the one end of the coil spring is also turned. Move. At this time, since the engaging protrusion cannot rotate due to the frictional force, the engaging protrusion is pressed against the other end of the coil spring with a gap between the engaging protrusion and one end of the coil spring. , The sector gear rotates via the pinion, and the seat pan can be lowered via the link. [0011] However, when it descends beyond a certain point, the relationship of rotational force> frictional force is established, so that the engaging projection which has been pushed and rotated by the other end of the coil spring is turned by the rotational force. The seat pan is rotated by the gap until it comes into contact with one end of the spring, and this rotation causes the seat pan to descend at a stretch, causing a problem that this acts as discomfort to the occupant. Therefore, the range of frictional force> rotational force could not be used as the lift range. Therefore, the present invention solves the above-mentioned disadvantages,
It is an object of the present invention to provide a vehicle seat lifter device in which the rotation range of a sector gear is widely used to reduce the size of the device and increase the range of elevation. [0013] A vehicle lifter device according to the present invention is a link and sector gear rotatable between a seat pan on which a seat cushion is mounted and a base plate mounted on a vehicle body. In the vehicle seat lifter device for moving the seat pan up and down by rotating the sector gear through a spring brake device having a pinion meshing with the sector gear, the rotation of the sector gear and the link A spring is wound around a shaft portion, and one end of the spring is locked to the link side, and the other end is locked to the sector gear side, so that the link is urged to rotate in the downward direction. I do. Therefore, even in the vicinity of the highest position of the seat pan, the sector gear is urged to rotate in the downward direction by the urging force of the spring, and the pinion of the spring brake device engaged with the sector gear always moves in the downward direction. It is rotationally biased. Therefore, in the spring brake device, a state is formed in which the engagement projection integrally formed with the pinion always pushes one end of the spring, and the engagement projection is provided with a clearance from the other end to the one end of the coil spring. No more rotation. Thus, even if the rotation range of the sector gear is enlarged, the occupant does not feel discomfort, and the vertical range can be increased and the size of the vehicle seat lifter device can be reduced. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of a vehicle seat lifter device, 1 is a seat pan on which a seat cushion (not shown) is mounted, and 2 is a bracket on which a seat pan 1 is mounted at a front portion thereof and is rotated by a shaft 3. The upper end of the link 4 is pivotally supported as much as possible. 5 is a shaft 6 at the lower end of the link 4
The sector gear 5 is rotatably mounted on a shaft. The sector gear 5 has a shaft portion 9 on a base plate 8 formed in a vertical wall shape on an upper rail of a seat slide device mounted on the vehicle body in a pair of right and left in the longitudinal direction. To be rotatable. One end portion 10a is locked to the shaft portion 9 and extended toward the shaft portion 6, wound around the shaft portion 6, and the other end portion 10b is extended toward the shaft portion 3 to engage with one end surface of the link 4. Spring spring 10
Are arranged. As shown in FIG. 2, the spring 10 has a gap between one end face of the link 4 and the other end 10b when the spring 10 is at the lowest position. By rotating in the counterclockwise direction in the figure, the link 4 is lifted upward and rises, and rotates until a state as shown in FIG. 3, that is, a state in which the shaft portions 3, 6, 9 are substantially aligned. In the process, one end face of the link 4 abuts on the other end 10b, and further rises, so that the spring spring 10 bends and urges the link 4 to rotate counterclockwise in the drawing. The rotational urging force of the link 4 urges the sector gear 5 to rotate clockwise in the drawing, and this direction is a direction in which the link 4 is lowered. The sector gear 5 has teeth 11 formed in a fan-shaped arc around the shaft 9, and a spring brake device 1 having a pinion 12 meshed with the teeth 11.
3 is fixed to a base plate 8. As shown in FIG. 4, the spring brake device 13 has an outer cylindrical housing 20 fixed to a side surface of the base plate 8 via a tripod mounting portion 19, and is housed in the cylindrical housing 20. Coil spring 21
And a pinion 12 integrally fixed with an engagement protrusion 25 rotatably inserted into one end 24a of the shaft 24. The shaft 24 is formed of a cylindrical housing 20. Is rotatably supported by the bearing portion 20b. As shown in FIG.
Reference numeral 1 denotes an outer peripheral surface that is in contact with the inner peripheral surface of the outer cylindrical housing 20, and both ends 21 a and 21 b of the core 23 are bent inward and disposed in a cutout portion 22 formed in the core 23.
A predetermined gap is provided between both ends 23a, 23b of the coil spring 21 and both ends 21a, 21b of the coil spring 21. An engagement protrusion 25 is disposed between the two ends 21a and 21b of the coil spring 21 with a gap.
An operation handle 26 is mounted on the other end 24b of the shaft 24 protruding outward from the cylindrical housing 20. At the rear of the seat pan 1, a link 15 rotatably supported by a shaft 17 on a bracket 14 on which the seat pan 1 is mounted is mounted on the base bracket 8 by a shaft 16
The link 15 is rotatably supported.
Is rotatably mounted on the sector gear 5a at the other end of the connecting link 18, and the sector gear 5a is rotatably mounted on the base plate 8 at the shaft 9a. It is supported. The spring brake device 13 has the same structure as that described above. Next, the operation of the vehicle seat lifter device having the above configuration will be described. When the operation handle 26 is rotated forward to rotate the shaft 24 forward (direction B in FIG. 5) in order to raise the seat cushion. In 5, the core 2
3 is one end 21a of the coil spring 21
Is pressed in the direction shown by the arrow, while the engagement projection 25 is
Inside, the one end 21a is pushed in the same direction and rotates, and at this time, the coil spring 21 slides so that the diameter is reduced by the one end 21a being pulled. As a result, the shaft 24 rotates smoothly within the cylindrical housing 20, and the shaft 24 shown in FIG.
, The pinion 12 rotates the sector gear 5 counterclockwise around the shaft 9 via the teeth 11, and one end of the link 4 moves along the trajectory of the shaft 6 to link 4. The bracket supporting the other end of the seat pan is pushed upward to raise the seat pan 1. The load of the occupant input from the seat pan 1 to the sector gear 5 via the link 4 is converted into a force for rotating the pinion 12 via the teeth 11 of the sector gear 5, and the engagement projection 25 Pushes one end 21a of the main spring 21 toward the end 23a of the core 23 which is stationary in the missing circular portion 22 (in the direction of arrow A).
The main spring 21 expands in diameter because the separation distance between the pinion 12 and the other end 21b increases, and the main spring 21 presses against the inner peripheral surface 20a of the cylindrical housing 20 to increase frictional resistance, thereby preventing the reverse rotation of the pinion 12. And the seat pan 1
Keeps the set height of the seat cushion without descending. Then, for example, the seat pan 1 is raised to the highest position, and as shown in FIG. 3, before the shafts 3, 6, 9 are aligned in a straight line, the spring 4 causes the link 4 to move in the descending direction. Energizing rotation. When the seat pan 1 is lowered from this state, when the operation handle 26 is rotated and the shaft 24 is rotated in the opposite direction, the end 23 b of the core 23 is moved to the other end 21 of the coil spring 21.
b is rotated so as to reduce the diameter.
1a also rotates in the circumferential direction. At this time, since the link 4 and the sector gear 5 are urged to rotate in the downward direction by the spring 10, the one end 2 of the coil spring 21 is
As soon as 1a moves, the pinion 12 and the engaging projection 2
5 rotates, and the engagement projection 25 is held in contact with the one end 21a. When the link 4 and the sector gear 5 reach a state of being bent to some extent, the spring 1
Although the urging force of 0 is not applied, the load applied via the bracket 2 urges the link 4 to rotate downward, so that the seat pan 1 can be lowered in the same manner. Thus, as shown by the shaded portion in FIG.
Spring spring 10 operating within the range of frictional force> rotational force
By using the pinion 12 and the sector gear 5
Can always be urged to rotate in the descending direction, so that the engagement projection 25 can be kept in a state of being constantly in contact with the one end 21a of the main spring 21 and the seat pan 1 can be held.
It is possible to eliminate the discomfort of the occupant caused when the vehicle descends at a stretch. . According to the present invention described above, the operating range of the conventional sector gear is provided by providing a spring spring for urging the sector gear to rotate downward in the vicinity of the highest position of the seat pan. The operating range of the sector gear can be extended to the part that could not be used as a. As a result, it is possible to increase the range of elevation of the vehicle seat lifter device and to reduce the size of the device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration side view of a seat lifter showing an embodiment of the present invention. FIG. 2 is a front view showing a main configuration of the present invention. FIG. 3 is an operation explanatory view of the present invention. FIG. 4 is an exploded perspective view of the spring brake device. FIG. 5 is a radial sectional view of the spring brake device. FIG. 6 is a diagram illustrating the operation of the present invention. [Description of Signs] 1 ... Seat pan 2 ... Brackets 3, 6, 9 ... Shaft 4 ... Link 5 ... Sector gear 8 ... Base plate 10 ... Spring spring 11 ... Tooth 12 ... Pinion 13 ... Spring brake device 20 ... Cylindrical Housing 21 ... Coil spring 23 ... Core 24 ... Shaft 25 ... Engaging projection 26 ... Operation handle

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-10-35332 (JP, A) JP-A-7-52696 (JP, A) JP-A-6-336133 (JP, A) 37026 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60N 2/00-2/72

Claims (1)

(57) [Claim 1] A seat pan on which a seat cushion is mounted and a base plate mounted on a vehicle body are connected by a rotatable link and a sector gear, and mesh with the sector gear. In a vehicle seat lifter device for moving the seat pan up and down by rotating a sector gear via a spring brake device having a pinion, a spring spring is wound around a rotation shaft portion of the sector gear and the link. A seat lifter device for a vehicle, wherein one end of the lever is locked on the link side and the other end is locked on the sector gear side to urge the link to rotate in the downward direction.